The Arab League's support for military intervention in Libya has been pivotal in persuading the US and the UN security council to act. But a glance through membership reveals that the governments of 18 of its 22 states do not have democratic credentials: they are suppressing – often violently – protest movements inside their own borders, have already undergone popular revolutions or have a chequered history regarding their support for democracy.

Libya

Currently suspended from the league because of Muammar Gaddafi's brutal suppression of the popular uprising. Protests spread to Libya in February, when security forces reportedly shot 35 protesters. In the ensuing unrest, Benghazi and other cities quickly fell into the hands of anti-government forces. By early March, it looked as if the oppositon would topple Gaddafi, but the Middle East's longest-serving autocrat hit back. His forces, backed by aircraft, tanks and heavy artillery, started to retake territory. Only air strikes authorised by the UN security council prevented Gaddafi from capturing Benghazi.

Egypt

Egyptians have overwhelmingly endorsed amendments to the constitution that will provide a blueprint for parliamentary and presidential elections to be held within the next six months. The vote followed mass protests in Cairo's Tahrir Square that forced Hosni Mubarak to step down as president on 11 February. Demonstrators continue to protest to ensure the new military rulers carry out promises of reform and their protests have forced out Ahmed Shafiq, who was appointed prime minister by Mubarak. Essam Sharaf, his successor, visited Tahrir Square, to pledge that he will work to meet protesters' demands.

Yemen

A military showdown looms after the defence minister announced that the army would defend President Ali Abdullah Saleh against any "coup against democracy". Saleh, however, looks increasingly isolated as military commanders, diplomats and MPs have either quit or declared their allegiance to the protesters. The army split followed Saleh's decision to sack his entire cabinet after snipers fired on demonstrators on Sunday, killing at least 52 people. The president and his sons still have control over powerful sections of the military. The instability in Yemen is a headache for the US as it has depended on Saleh to stamp out al-Qaida operatives who have taken refuge there.

Bahrain

The government imposed a three-month period of martial law this month after weeks of violent clashes between citizens and riot police. The clashes have taken on a sectarian tone. The kingdom, which is ruled by Sunnis but has a Shia majority, is anxious to play these down. Bahrain's rulers claim to have uncovered a plot involving outside powers – an implicit reference to neighbouring Iran. The government asked Iranian diplomats to leave the tiny Gulf state and later accused Lebanon's Hezbollah of destabilising the region and impinging on Bahrain's sovereignty. A decision to call in troops from Saudi Arabia, the United Arab Emirates and other Sunni-ruled Gulf states has inflamed tensions.

Tunisia

In the country where the "Arab spring" started, a court has ruled that the party of former President Zine al-Abidine Ben Ali be dissolved, clearing away one of the last vestiges of the regime that ruled Tunisia for two decades. Ben Ali was toppled by mass protests in January after an unemployed graduate set himself alight. An election has been called for 24 July to choose a national assembly that will rewrite the constitution. Meanwhile, Ben Ali's secret police service, a domestic spy agency notorious for human rights abuses, has been dismantled.

Morocco

Morocco shares some of the key trends that fanned the flames of revolution in Tunisia and Egypt. They include a young, internet-savvy population confronted by endemic corruption and what some call hogra – humiliation by the state. In the latest protests, hundreds of teachers marched through Rabat on Monday for better pay, a day after one of Morocco's largest protests in recent decades against corruption. They demanded a change of government. "As in other countries of the region, Morocco is asking itself whether its economic or political foundations are not among the worst," L'Economiste, a daily business newspaper, said in an editorial this week. "There is a need for the social contract to be renewed."

Saudi Arabia

King Abdullah has promised a multibillion-pound package of reforms, pay rises, cash, loans and housing, even though protests have been limited in the oil-rich kingdom. Saudi demonstrators have mostly come from the Shia-dominated eastern area. They share similar grievances to their fellow Shias in neighbouring Bahrain. But the changes announced by Abdullah did not loosen the monarchy's tight hold on power, a key demand of Saudi opposition figures.

Syria

At least five people died last week in the southern city of Dera'a in the worst violence in Syria since 2004 when at least 25 people died. President Bashar al-Assad told the Wall Street Journal in February that Syria was insulated from the upheaval in the Arab world because the leadership was not out of touch with the people and because of its strong stand against Israel. But analysts say the unrest could escalate into something much bigger and more decisive, with the regime's own reactions – now consisting of the usual brute force with a novel, nervous dose of conciliation – constituting the key factor as to whether it does or not.

Oman

The normally sleepy Gulf state has just carried out its third cabinet reshuffle in a month in the latest of a string of concessions to appease protesters demanding jobs and political reforms. Sultan Qaboos bin Said has promised 50,000 new jobs and other benefits to ward off unrest.

Jordan

In February King Abdullah swore in a new government, led by a former general who has promised to widen public freedoms in response to anti-government protests. Scores of such demonstrations have been staged, with a mix of tribal- and Islamist-led opposition calling for moves towards a constitutional monarchy that limits the powers of the throne.

Kuwait

Protesters say they want Sheikh Nasser al-Mohammad al-Sabah to resign as prime minister but do not want to overthrow the whole regime. Last month, about 1,000 stateless residents, known as bedoun, protested west of Kuwait City to demand improved rights. Tensions eased after legislators vowed to discuss a draft law that would grant them basic civil rights.

Algeria

Thousands of people have taken to the streets and numerous strikes have been held since unrest erupted in neighbouring Tunisia. To placate demonstrators, President Abdelaziz Bouteflika, who was elected in 1999, last month lifted the state of emergency which had been in place since 1992 to combat an insurgency by Islamist extremists that has killed about 200,000 people. A long-standing ban on protests in Algiers, however, remains in place, although demonstrations have taken place.

Comoros

The country has had a history marked by numerous coups d'état since independence in 1975. Colonel Mohammed Bacar, a French-trained former gendarme, seized power as president in one of the four islands, Anjouan, in 2001. He fled in March 2008, when hundreds of soldiers from the African Union and Comoros took back Anjouan.

Lebanon

Bedevilled by sectarian grudges, Lebanon experienced its worst political crisis in three years in January, when Najib Miqati, a Syrian-backed businessman, was sworn in as prime minister, replacing Saad Hariri. Once an international tribunal investigating the assassination of former prime minister, Rafiq Hariri, indicts members of Hezbollah as expected, there are fears of renewed violence .

Djibouti

In February, protesters demanded that President Ismaïl Omar Guelleh, who was elected in 1999, step down.

Somalia

The weak government has been fighting Islamist insurgents for the past two years. It launched an offensive against al-Shabab militants linked to al-Qaida, involving 17,000 African Union and Somali troops to reclaim territories, starting with the capital, Mogadishu.

United Arab Emirates

To pre-empt dissent, Sheik Mohammed bin Zayed al-Nahyan, crown prince of Abu Dhabi, last month toured the country to gauge the public mood. Afterwards, he ordered a $1.5bn investment in electricity and water projects in the northern emirates. It is one of the few Arab states to have said it will contribute to the military action enforcing the Libya no-fly zone.

Mauritania

Several thousand young demonstrators rallied in the capital, Nouakchott, in early March to demand economic, political and social reforms.

• The remaining three members of the league are Qatar (which has also said it will participate in the no-fly zone), the Palestinian Authority and Iraq.

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